TABLE 14 Mortality of 1,479 Children Born in Eleven Punjab Villages, by Interval between Observed and Preceding Child, India, 1955-1958 Interval Neonatal Mortality: Infant Mortality: Second Year between Number Deaths per 1,000 Deaths per 1,000 Mortality: Births in of Infants Aged Less Population Aged Deaths per 1,000 Months Births Than 28 Daysa Less Than 1 Yearb Population0 Primipara 231 95.2 175.4 68.7 0-11 34 88.2 205.9 105.3 12-23 432 97.2 201.9 54.9 24-35 491 57.0 132.2 89.0 36-47 175 57.1 137.9 57.7 48+ 112 35.7 108.1 29.0 Unknown 4 0.0 0.0 0.0 Total 1,479 73.7 160.6 67.9 aNumber = 1479. Number = 1457. c Number = 854. Source: Gordon et al. (63). weaning occur earlier with the consequent weanling diarrhea so often seen in developing countries (64). The younger he is when this occurs, the more serious the consequences are likely to be. During the period of their study the index children who could be observed for a sufficient length of time after the birth of a subsequent sibling were few in number. The authors report the following, however: From the data which exist, the suggestion is that the effect of a short birth interval is more marked for the first child of a pair than it is for the second, as definite as that is. (63, p. 372) Birth Interval and Morbidity. No studies of the association between acute illness and birth interval have been found. As remarked earlier, however, death is the extreme end of the spectrum of morbid processes, and the clear-cut associations between mortality rates and birth interval in the post-neonatal and l-to-4-year age groups seen above would surely lead us to expect an increase in illness among closely spaced children. With regard to more chronic processes—malnutrition, for example-Gordon's remarks above (63) concerning the effects of interval on the preceding child are particularly relevant. It is also pertinent to note that one of the most severe forms of malnutrition seen in developing countries was called kwashiorkor by Williams when she first reported it in 1935 (65). In discussing rhis mnnv vftars latftr (f\(\\. she rennrtfid that in thp. Afrirjin trihtil Innonnootion, but it seems likely that many mothers in such situations would receive less than optimal prenatal care and be subject to more emotional stress than mothers who conceive their first child after marriage.